Martin, was African-American. The man who shot him, George Zimmerman, is white with Hispanic roots on his mother's side. Zimmerman says he acted in self defense. Martin's family and supporters say the self-styled neighborhood watch volunteer profiled the teenager and followed him.

On Monday's edition of Tell Me More, Trayvon's mother tells host Michel Martin that what happened to her son should not be "about black and white."

She is hoping, Sybrina Fulton said, not only for "justice" in her son's case, but also for changes in stand your ground laws — so that "you cannot follow, pursue [or] chase anyone ... be the aggressor ... shoot and kill them ... and then go home to your bed." Fulton is pushing for a "Trayvon Martin" amendment to add those conditions to stand your ground laws.

Zimmerman's trial on a charge of second-degree murder is set to start on June 10. An important hearing comes first. On April 29, a judge is due to hear arguments about whether Zimmerman should be able to claim self defense immunity because of Florida's stand your ground law.

Benjamin Crump, the attorney representing Trayvon's family, tells Michel that if the judge rules in Zimmerman's favor in that April hearing, the criminal case will effectively be over.

Much more from Michel's conversation with Fulton and Crump will be on Tell Me More later. Click here to find an NPR station that broadcasts the show.